Brooks, Emma G.E.; Roberton, Scott I.; Bell, Diana J. (2010). "The conservation impact of commercial wildlife farming of porcupines in Vietnam". Biological Conservation. 143 (11): 2808. Bibcode:2010BCons.143.2808B. doi:10.1016/j.biocon.2010.07.030.
Meredith R. W.; Janecka J. E.; Gatesy J.; Ryder O. A.; Fisher C. A.; Teeling E. C.; Goodbla A.; Eizirik E.; Simao T. L.; Stadler T.; Rabosky D. L.; Honeycutt R. L.; Flynn J. J.; Ingram C. M.; Steiner C.; Williams T. L.; Robinson T. J.; Burk-Herrick A.; Westerman M.; Ayoub N. A.; Springer M. S.; Murphy W. J. (2011). "Impacts of the Cretaceous terrestrial revolution and KPg extinction on mammal diversification". Science. 334 (6055): 521–524. Bibcode:2011Sci...334..521M. doi:10.1126/science.1211028. PMID21940861. S2CID38120449.
Brooks, Emma G.E.; Roberton, Scott I.; Bell, Diana J. (2010). "The conservation impact of commercial wildlife farming of porcupines in Vietnam". Biological Conservation. 143 (11): 2808. Bibcode:2010BCons.143.2808B. doi:10.1016/j.biocon.2010.07.030.
Meredith R. W.; Janecka J. E.; Gatesy J.; Ryder O. A.; Fisher C. A.; Teeling E. C.; Goodbla A.; Eizirik E.; Simao T. L.; Stadler T.; Rabosky D. L.; Honeycutt R. L.; Flynn J. J.; Ingram C. M.; Steiner C.; Williams T. L.; Robinson T. J.; Burk-Herrick A.; Westerman M.; Ayoub N. A.; Springer M. S.; Murphy W. J. (2011). "Impacts of the Cretaceous terrestrial revolution and KPg extinction on mammal diversification". Science. 334 (6055): 521–524. Bibcode:2011Sci...334..521M. doi:10.1126/science.1211028. PMID21940861. S2CID38120449.
Meredith R. W.; Janecka J. E.; Gatesy J.; Ryder O. A.; Fisher C. A.; Teeling E. C.; Goodbla A.; Eizirik E.; Simao T. L.; Stadler T.; Rabosky D. L.; Honeycutt R. L.; Flynn J. J.; Ingram C. M.; Steiner C.; Williams T. L.; Robinson T. J.; Burk-Herrick A.; Westerman M.; Ayoub N. A.; Springer M. S.; Murphy W. J. (2011). "Impacts of the Cretaceous terrestrial revolution and KPg extinction on mammal diversification". Science. 334 (6055): 521–524. Bibcode:2011Sci...334..521M. doi:10.1126/science.1211028. PMID21940861. S2CID38120449.
Meredith R. W.; Janecka J. E.; Gatesy J.; Ryder O. A.; Fisher C. A.; Teeling E. C.; Goodbla A.; Eizirik E.; Simao T. L.; Stadler T.; Rabosky D. L.; Honeycutt R. L.; Flynn J. J.; Ingram C. M.; Steiner C.; Williams T. L.; Robinson T. J.; Burk-Herrick A.; Westerman M.; Ayoub N. A.; Springer M. S.; Murphy W. J. (2011). "Impacts of the Cretaceous terrestrial revolution and KPg extinction on mammal diversification". Science. 334 (6055): 521–524. Bibcode:2011Sci...334..521M. doi:10.1126/science.1211028. PMID21940861. S2CID38120449.
si.edu
nationalzoo.si.edu
Smithsonian's National Zoo & Conservation Biology Institute (2017-03-03). "Curious About Quills".
Flower, William Henry; Lydekker, Richard (1911). "Porcupine" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 22 (11th ed.). Cambridge University Press. p. 101 second para. The spines are mixed with long soft hairs